Treating of animal-skin products



Patented Oia. 7, ,1930

UNITED s'rA- TEs PATIENT- OFF mromo rnnnn'r'rr, or. MILAN, ITALY,ilssrorron. zro socm'ra mvnnzrom nnnvn'r'rr ANONIMA TORINO, or 'runm,ITALY TREATING or ANIMAL-SKIN raonuo'rs Ho Drawing. Original applicationmea m 24, 1929, Serial No. 385,780, andin ma J'nly 14, ms.

' Divided and this application filed m 15, mo. Serial No. 468,122.

This invention relates to a process of treating animal skin materials oranimal skin products, as distinguished from the treatment of wool, hair,etc, and has for one of its objects the provision of a process adaptedfor utilizing scraps and cuttings from tanned hides, whereby suchmaterials may be converted into a useful and valuable product which vinappearance, fibrous texture I and flexibility resembles natural leather.

It will at once be apparent that my invention is of great economicalvalue in that it salvages or'utilizes materials which heretofore havegenerally been converted into glues or fertilizers-or simply thrownaway.

In .the' practice of my invention the mate rial to be treated, such ascuttings and scraps 3 from' chrome tannedleather for instance, is

first subjected to apreliminary neutralization if the acid has notyetbeen eliminated 'from the material, byv treatment with a neutralizingagent such for example, as an alkaline salt of a weak acid, neutrol forexample, a composition two-thirds bicarbonate of soda and one-thirdsodium sulphate, borate of sodium, sodium hypo'sulfite, bicarbonate rialcontaining a water insoluble binder to.

of soda, either separately or combined, at a temperature between 309 and(1, for example. v I I v The material is then washed and mechanicallyand intimately admixed with water until a. slurry with the fibers of thematerial in suspension is obtained.- To this slurry I add a grease oroil'of-such I a. nature as to be'capable of emulsifying when added-totheslurr an example of a suitable reaseor oil-being chromine, thismaterial 'ing added at a temperature between 30 and 609 order that thefibers of the i ultimatelymay be 'bondedor united toeach other I add asuitable. binding mate- 'the slurry,- the binding material beingmiscible with water prior to coagulation of the- ;binder; thisbinder maybe indiarrubber latex, gutta like as'obtamed 'fromthe' trees and whichrcha latex, ,balata'latex or the v may have been preserved by ammonia orany other suitable alkaline preserving material.

A synthetic latex or. other binding material containing a waterinsoluble binder and in suitable condition'for incorporation in theslurry may be substituted for the latices above mentioned.

As a preservative for the latex,-when latex is employed as a binder, avegetable tannage such as sumac is added to the slurry.

The slurry is now deposited upon a suitable perforated support such as awire gauze and the liquid of the slurry abstracted so that a sheet offibers is obtained containing a water, insoluble binder. The materialmay then be rolled and pressed and subjected to the usual finishingoperations employed in the finishing of natural leathers.

Inasmuch as the liquid of'the slurry is finally abstracted, as abovepointed out, I may add .to the slurry a material such as commer- It willbe understood that the amount of sodium chloride, or the like, employedwill vary depending upon the material being treated and upon theseparation'or abstracting of the liquid of the slurry that is desired.

Ifind that in the practice of my invention some care mustbe exercised soas not to a] such detrimentalcoagulation renders the final steps of theprocess as well asthepro'perties of the finished'product unsatisfactory.

'low coagulation of the biiider employed to When employing latex as abinding material I prefer to abstract the liquid of the slurry within anhour'of the addition of the bind ing materialr' This application isa'division of my copending application Serial No. 365,780, filed May24,1929. y 4

What I claim is i 1. The process whieheoniprises treating mineral tannedanimal skin products with a neutralizing agent, Washing, eflectin anintimate admixture of the material t us obtained and an aqueous mediumuntil a flowing slurry with the tanned fibers of'the animal skinproducts in suspension is obtained, adding a grease and thereupon awater insoluble binder and a preservative therefor, and then abstractingthe liquid from the slurry.

2. The process which comprises treating mineral tanned animal skinproducts with a neutralizing agent, washing, eflecting an intimateadmixture of the material thus obtained and an aqueous medium until aflowing slurry with the tanned fibers of the animal skin products insuspension is obtained,

adding a grease, vegetable tannin and latex,

and abstracting the liquid of the slurry.

3. The process which comprises treating mineral tanned animal skinproducts with an alkaline salt of a weak acid, eifecting an intimateadmixture of the material thus obtained and an aqueous medium until aflowing slurry with the tanned'fibers of the animal skin products insuspension is obtained, add-' ing a grease, a water insoluble binder anda preservative therefor, and then abstracting the liquid from theslurry.

4. The process which comprises treating mineral tanned animal'skinproducts with a composition bicarbonate of soda and sodium sulphate,washing, effecting an intimate admixture of the material thus obtainedand an aqueous medium until a flowing slurry with the tanned fibers ofthe animal skin products in suspension is obtained, adding a grease, avegetable tannin and latex, and abstracting the liquid of the slurry.

5. The process which comprises treating mineral tanned animal skinproducts with a neutralizing agent, washing, effecting an intimateadmixture of the material thus obtained and an aqueous medium until aflowing slurry with the tanned fibers of the animal skin products insuspension is obtained, adding a rease, sodium chloride, a waterinsoluble b nder and a preservative therefor, and abstracting theliquidfromthe slurry.

6. The process which comprises treating mineral tanned animal skinproducts with a neutralizing agent, washing, effecting an intimateadmixture-of the-material thus obtained and an aqueous medium until aflowing slurry with the tanned fibers of the animal skin products, insuspension is obtained,

adding a grease, vegetable tannin, latex and sodium chloride'to theslurry, and abstracting the liquid of the slurry.

7. The process which comprises treating mineral tanned animal skinproducts with an alkaline salt of a weak acid, effecting an intimateadmixture of the material thus obtained and an aqueous medium until aflowing slurry with the tanned fibers of the aniadding chloride to theslurry, and abstractingthe liquid of the slurry. 1

9. The process which comprises treating mineral tanned animal skinproducts with a neutralizing agent at a temperature between 30 and 60(3., washing, effecting an intimate admixture of the material thusobtained and an aqueous medium until a flowing slurry with the tannedfibers of the animal skin products in suspension is obtained, adding agrease, a water insoluble binder and a preservatlve for the binder, andthen abstracting the liquid from the slurry.

10. The process which comprises treating mineral tanned animal skinproducts with a neutralizing agent, washing, effecting an in timateadmixture of the material thus obtained and an aqueous medium until aflowing slurry with the tanned fibers of the animal skin products insuspension is obtained,

and 60 and thereupon a water insoluble binder and a preservativetherefor, and then abstracting the liquid from the slurry.

This specificat on signed this 21st day of J ime, 1930.

ANTONTO FERRET'IL a (grease at a temperature between 50 Inn

